Note 10 - Fair Value Measurement (Details) - Assets Measured at Fair Value on a Recurring Basis (USD $)	Mar. 31, 2015	Dec. 31, 2014
Securities available for sale:
Securities available for sale	$ 272,483,000us-gaap_AvailableForSaleSecurities	$ 292,299,000us-gaap_AvailableForSaleSecurities
Bank-owned life insurance	15,252,228us-gaap_BankOwnedLifeInsurance	15,125,498us-gaap_BankOwnedLifeInsurance
Forward Contracts [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Forward starting interest rate swap	(509,000)	(405,000)
Forward Contracts [Member] \| Interest Rate Swap [Member] \| Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Forward starting interest rate swap	(509,000)	(405,000)
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Securities available for sale	31,659,000	31,232,000
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Securities available for sale	31,659,000	31,232,000
US Government Agencies Debt Securities [Member]
Securities available for sale:
Securities available for sale	31,659,000	31,232,000
Mortgage Backed [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Securities available for sale	156,089,000	174,280,000
Mortgage Backed [Member] \| Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Securities available for sale	156,089,000	174,280,000
Mortgage Backed [Member]
Securities available for sale:
Securities available for sale	156,089,000	174,280,000
Municipal Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Securities available for sale	55,921,000	55,702,000
Municipal Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Securities available for sale	55,921,000	55,702,000
Municipal Securities [Member]
Securities available for sale:
Securities available for sale	55,921,000	55,702,000
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Securities available for sale	28,814,000	31,085,000
Corporate Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Securities available for sale	28,814,000	31,085,000
Corporate Debt Securities [Member]
Securities available for sale:
Securities available for sale	28,814,000	31,085,000
Mortgage Loans Held For Sale [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Securities available for sale	7,947,000	4,793,000
Mortgage Loans Held For Sale [Member] \| Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Securities available for sale	7,947,000	4,793,000
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Total	31,659,000	31,232,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Securities available for sale	31,659,000	31,232,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale:
Bank-owned life insurance	15,252,000	15,125,000
Total	263,514,000	280,580,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Securities available for sale	240,824,000	261,067,000
Bank-owned life insurance	15,252,000	15,125,000
Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value Measurement [Member]
Securities available for sale:
Bank-owned life insurance	15,252,000	15,125,000
Total	$ 295,173,000	$ 311,812,000

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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-Section S99

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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